diff options
Diffstat (limited to 'zcat.cc')
| -rw-r--r-- | zcat.cc | 106 |
1 files changed, 51 insertions, 55 deletions
@@ -1,18 +1,18 @@ -/* Zcat - decompress and concatenate files to standard output - Copyright (C) 2010-2019 Antonio Diaz Diaz. +/* Zcat - decompress and concatenate files to standard output + Copyright (C) 2010-2020 Antonio Diaz Diaz. - This program is free software: you can redistribute it and/or modify - it under the terms of the GNU General Public License as published by - the Free Software Foundation, either version 2 of the License, or - (at your option) any later version. + This program is free software: you can redistribute it and/or modify + it under the terms of the GNU General Public License as published by + the Free Software Foundation, either version 2 of the License, or + (at your option) any later version. - This program is distributed in the hope that it will be useful, - but WITHOUT ANY WARRANTY; without even the implied warranty of - MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the - GNU General Public License for more details. + This program is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + GNU General Public License for more details. - You should have received a copy of the GNU General Public License - along with this program. If not, see <http://www.gnu.org/licenses/>. + You should have received a copy of the GNU General Public License + along with this program. If not, see <http://www.gnu.org/licenses/>. */ #define _FILE_OFFSET_BITS 64 @@ -90,19 +90,21 @@ Line_number line_number; void show_help() { - std::printf( "Zcat copies each given file to standard output. If any given file is\n" - "compressed, its decompressed content is used. If a given file does not\n" - "exist, and its name does not end with one of the known extensions, zcat\n" - "tries the compressed file names corresponding to the formats supported.\n" + std::printf( "zcat copies each file argument to standard output in sequence. If any\n" + "file given is compressed, its decompressed content is copied. If a file\n" + "given does not exist, and its name does not end with one of the known\n" + "extensions, zcat tries the compressed file names corresponding to the\n" + "formats supported. If a file fails to decompress, zcat continues copying the\n" + "rest of the files.\n" "\nIf a file is specified as '-', data are read from standard input,\n" "decompressed if needed, and sent to standard output. Data read from\n" "standard input must be of the same type; all uncompressed or all in the\n" - "same compression format.\n" + "same compressed format.\n" "\nIf no files are specified, recursive searches examine the current\n" "working directory, and nonrecursive searches read standard input.\n" - "\nThe formats supported are bzip2, gzip, lzip and xz.\n" + "\nThe formats supported are bzip2, gzip, lzip, and xz.\n" "\nUsage: zcat [options] [files]\n" - "\nExit status is 0 if no errors occurred, non-zero otherwise.\n" + "\nExit status is 0 if no errors occurred, 1 otherwise.\n" "\nOptions:\n" " -h, --help display this help and exit\n" " -V, --version output version information and exit\n" @@ -113,7 +115,7 @@ void show_help() " -M, --format=<list> process only the formats in <list>\n" " -n, --number number all output lines\n" " -N, --no-rcfile don't read runtime configuration file\n" - " -O, --force-format=<fmt> force given format (bz2, gz, lz, xz)\n" + " -O, --force-format=<fmt> force the format given (bz2, gz, lz, xz)\n" " -q, --quiet suppress all messages\n" " -r, --recursive operate recursively on directories\n" " -R, --dereference-recursive recursively follow symbolic links\n" @@ -130,10 +132,10 @@ void show_help() } -int do_cat( const int infd, const int buffer_size, - uint8_t * const inbuf, uint8_t * const outbuf, - const std::string & input_filename, - const Cat_options & cat_options ) +bool do_cat( const int infd, const int buffer_size, + uint8_t * const inbuf, uint8_t * const outbuf, + const std::string & input_filename, + const Cat_options & cat_options ) { static int at_bol = 1; // at begin of line. 0 = false, 1 = true, // 2 = at begin of second blank line. @@ -148,7 +150,7 @@ int do_cat( const int infd, const int buffer_size, if( outpos >= buffer_size ) { if( writeblock( STDOUT_FILENO, outbuf, outpos ) != outpos ) - { show_error( "Write error", errno ); return 1; } + { show_error( "Write error", errno ); return false; } outpos = 0; } if( inpos > rd ) // inbuf is empty @@ -157,14 +159,14 @@ int do_cat( const int infd, const int buffer_size, if( rd != buffer_size && errno ) { show_file_error( input_filename.c_str(), "Read error", errno ); - return 1; + return false; } if( rd == 0 ) { if( writeblock( STDOUT_FILENO, outbuf, outpos ) != outpos ) - { show_error( "Write error", errno ); return 1; } + { show_error( "Write error", errno ); return false; } outpos = 0; - return 0; + return true; } inpos = 0; inbuf[rd] = '\n'; // sentinel newline @@ -226,32 +228,27 @@ int do_cat( const int infd, const int buffer_size, } -int cat( int infd, const int format_index, const std::string & input_filename, - const Cat_options & cat_options ) +bool cat( int infd, const int format_index, const std::string & input_filename, + const Cat_options & cat_options ) { enum { buffer_size = 4096, outbuf_size = (5 * buffer_size) + 256 + 1 }; - // buffer with space for sentinel newline at the end + // input buffer with space for sentinel newline at the end uint8_t * const inbuf = new uint8_t[buffer_size+1]; - // buffer with space for character quoting, 255-digit line number, + // output buffer with space for character quoting, 255-digit line number, // worst case flushing respect to inbuf, and a canary byte. uint8_t * const outbuf = new uint8_t[outbuf_size]; outbuf[outbuf_size-1] = 0; - int retval = 0; Children children; - if( !set_data_feeder( input_filename, &infd, children, format_index ) ) - retval = 1; - else - retval = do_cat( infd, buffer_size, inbuf, outbuf, - input_filename, cat_options ); - - if( !good_status( children, retval == 0 ) ) retval = 1; - - if( retval == 0 && close( infd ) != 0 ) - { show_close_error(); retval = 1; } - if( outbuf[outbuf_size-1] != 0 ) - internal_error( "buffer overflow." ); + bool error = false; + + if( !set_data_feeder( input_filename, &infd, children, format_index ) || + !do_cat( infd, buffer_size, inbuf, outbuf, input_filename, cat_options ) ) + error = true; + if( !good_status( children, !error ) ) error = true; + if( !error && close( infd ) != 0 ) { show_close_error(); error = true; } + if( outbuf[outbuf_size-1] != 0 ) internal_error( "buffer overflow." ); delete[] outbuf; delete[] inbuf; - return retval; + return !error; } } // end namespace @@ -264,8 +261,8 @@ int main( const int argc, const char * const argv[] ) int recursive = 0; // 1 = '-r', 2 = '-R' std::list< std::string > filenames; Cat_options cat_options; - invocation_name = argv[0]; program_name = "zcat"; + invocation_name = ( argc > 0 ) ? argv[0] : program_name; const Arg_parser::Option options[] = { @@ -357,16 +354,15 @@ int main( const int argc, const char * const argv[] ) if( filenames.empty() ) filenames.push_back( recursive ? "." : "-" ); std::string input_filename; - int retval = 0; bool error = false; bool stdin_used = false; while( next_filename( filenames, input_filename, error, recursive ) ) { int infd; - if( input_filename.empty() ) + if( input_filename == "." ) { if( stdin_used ) continue; else stdin_used = true; - infd = STDIN_FILENO; + infd = STDIN_FILENO; input_filename = "-"; } else { @@ -374,10 +370,11 @@ int main( const int argc, const char * const argv[] ) if( infd < 0 ) { error = true; continue; } } - const int tmp = cat( infd, format_index, input_filename, cat_options ); - if( tmp > retval ) retval = tmp; + if( !cat( infd, format_index, input_filename, cat_options ) ) error = true; - if( input_filename.size() ) close( infd ); + if( close( infd ) != 0 ) + { show_file_error( input_filename.c_str(), "Error closing input file", + errno ); error = true; } } if( std::fclose( stdout ) != 0 ) @@ -385,6 +382,5 @@ int main( const int argc, const char * const argv[] ) show_error( "Error closing stdout", errno ); error = true; } - if( error && retval == 0 ) retval = 1; - return retval; + return error; } |